The Gunners can move five points clear of fifth-placed Liverpool if Arsene Wenger’s side beat West Ham United at The Emirates on Saturday.
Arsenal have responded from their north London derby defeat in emphatic style, winning their last four Premier League games.
Sanchez, who is set to line up for Chile against Brazil at The Emirates on 29 March, isn’t getting complacent in the race to book a spot in next season’s Champions League.
“It’s all down to us,” Sanchez told Arsenal Player.
“If we want to stay in the top four or climb some places on the table we must maintain the winning mentality.
“I always say that mentality is a crucial aspect in a football environment. If a footballer goes on the pitch with the right mentality he will perform well.
Sanchez has scored 13 goals and has made seven assists in 25 Premier League appearances following his £35m switch to Emirates Stadium from La Liga side Barcelona last summer.
The former Udinese man has also scored three times in the Champions League this term, as well as bagging strikes in the FA Cup and League Cup.
Brazil v Chile is on March 29 at 15:00 GMT at the Emirates Stadium in London. Tickets are on sale at arsenal.com/tickets
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